Uncertainties and Inconsistencies

Quantitative Understanding of the Linkage

At present we are unaware of any well established quantitative relationships between ex vivo T production (as an indirect measure of theca cell T synthesis) and ex vivo E2 production (as an indirect measure of granulosa cell E2 synthesis). There are considerable data available which might support the development of such a relationship. Additionally, there are a number of existing mathematical/computational models of ovarian steroidogenesis that may be adaptable to support a quantitative understanding of this linkage (Breen et al. 2007; Shoemaker et al. 2010; Quignot and Bois 2013).

Response-response Relationship

Time-scale

Known modulating factors

Known Feedforward/Feedback loops influencing this KER

Domain of Applicability

Enzymes required for testosterone and 17ß-estradiol synthesis are only found in vertebrates and amphioxus (Markov et al. 2009; Baker 2011). They are not present in invertebrates. Consequently, this KER is not applicable to invertebrates.